The Relational Model and the Normal Forms of the Relational Model were first defined by Dr. E. F. Codd (Codd 1970), then extended by other writers after him. He invented the term “normalized relations” by borrowing from the political jargon of the day. A branch of mathematics called relations deals with mappings among sets defined by predicate calculus from formal logic. Just as in an algebraic equation, there are many forms of the same relational statement, but the “normal forms” of relations are certain formally defined desirable constructions. The goal of normal forms is to avoid certain data anomalies that can occur in unnormalized tables.

Data anomalies are easier to explain with an example, but first please be patient while ...

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